Portable telephone having a biased rotatable cover

ABSTRACT

A portable telephone having a cover (14) rotatably mounted to a cover body (2). When the cover (14) is in a closed condition, it covers and protects a switch section of the body (2), while when the cover (14) is in an open condition, it is held in a stable position at a predetermined inclined angle with respect to the body (2) by a cover holding mechanism. When the cover (14) is in the open condition, it also functions as a voice reflecting and collecting board for a microphone provided in the body (2).

This application is a continuation of application Ser. No. 08/434,121,filed May 2, 1995, now U.S. Pat. No. 5,692,045 which is a continuationof application Ser. No. 08/334,006, filed Nov. 2, 1994, now abandoned,which is a continuation of application Ser. No. 08/054,019, filed Apr.29, 1993, now abandoned, which is a continuation of application Ser. No.07/773,644, filed as PCT/JP91/00253 Feb. 26, 1991, U.S. Pat. No.5,257,310.

TECHNICAL FIELD

The present invention relates generally to a portable telephone, andmore particularly to the structure of a case of a portable telephonehaving a cover. In the following description, it is to be noted that theterm portable telephone used herein also includes a general cordlesstelephone.

BACKGROUND ART

An ultimate object of communication is, of course, to enable informationto be transmitted or exchanged at once anytime, from anywhere, and byanybody. In addition to conventional intercommunication between fixedpoints, mobile communication has been gradually developed. Mobilecommunication means a communication between a mobile body such as ship,automobile, or airplane (including a human being) and a fixed point suchas home or office, and also means an intercommunication between twomobile bodies. In recent years, a portable telephone or a cordlesstelephone as a kind of means for carrying out the mobile communicationhas been extensively developed.

In general, a telephone is used with a receiver section put to the earand a transmitter section kept near the mouth. So also in a portabletelephone, it is necessary to ensure a sufficient distance between thereceiver section and the transmitter section. In this circumstance, aconventional portable telephone itself is relatively long and large insize.

A portable telephone having a foldable cover for protecting a switchsection of the portable telephone is known. In this portable telephone,a microphone is provided in the cover so as to ensure a sufficientdistance between a speaker and the microphone.

In the above described conventional portable telephone, the distancebetween the receiver section and the transmitter section, both providedin a telephone body, is set to be substantially equal to the distancebetween the ear and the mouth of a user. Accordingly, such portabletelephone cannot be made sufficiently compact. A manufacturingtechnology for parts constituting the portable telephone has beenadvanced to supply compact and inexpensive parts. In this viewpointonly, a compact portable telephone can be manufactured relativelyeasily. However, since there exists a human engineering demand that thedistance between the receiver section and the transmitter section shouldbe substantially equal to that between the ear and the mouth, thisdemand causes a hindrance in practically manufacturing a compactportable telephone.

Further, in the conventionally proposed portable telephone having afoldable cover, since the microphone is provided in the cover, amicrophone cord is liable to break due to repeated opening and closingoperation of the cover.

It is accordingly an object of the present invention to provide aportable telephone which can ensure a sufficient distance between thereceiver section and the transmitter section during telephoniccommunication regardless of the compact construction of the telephonebody.

It is another object of the present invention to provide a portabletelephone which can protect the switch section in an inoperativecondition and improve an S/N characteristic in the transmitter sectionwhen in an operative condition.

DISCLOSURE OF THE INVENTION

According to the present invention, there is provided a portabletelephone comprising a body including a speaker, a microphone, andswitch means; a cover rotatably mounted to said body, said covercovering at least said switch means when said cover is in a closedcondition; and cover holding means for rotatably holding said cover withrespect to said body, said cover holding means including biasing meansfor exerting a biasing force to said cover so as to maintain said coverat a stable position in a rotational direction when said cover is in anopen condition.

Preferably, the cover holding means comprises a cover mountingprojection integrally formed with said body and having a pair of holes;a pair of shafts rotatably inserted through said holes, respectively,each of said shafts having one end fixed to said cover and having aplate portion formed near its other end; and a pair of U-shaped springsfixed to said body so as to respectively nip said plate portions of saidshafts.

In using the portable telephone, when the cover is opened, it is held ina stable position where the cover is inclined at a predetermined angle(e.g., 145°) with respect to the body by the cover holding means. Inthis stable position, the cover also functions as a voice reflecting andcollecting board.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view of a portable telephone according to a preferredembodiment of the present invention;

FIG. 2 is a side view of FIG. 1;

FIG. 3 is an exploded perspective view showing a first preferredembodiment of a cover holding mechanism according to the presentinvention;

FIG. 4 is a vertical sectional view showing stepwise rotationalpositions of the cover rotatably mounted to an upper case;

FIG. 5 is a bottom plan view of the upper case shown in FIG. 4 with thecover closed;

FIGS. 6A, 6B and 6C are cross sections taken along the lines 6--6 inFIG. 5, corresponding to cover positions "a", "b" and "c" shown in FIG.4;

FIG. 7 is a vertical sectional view showing a second preferredembodiment of a cover holding mechanism according to the presentinvention;

FIG. 8 is an enlarged view of a wave cam taken in the direction of arrowB shown in FIG. 7; and

FIG. 9 is a front elevational view of the wave cam shown in FIG. 8.

BEST MODE FOR CARRYING OUT THE INVENTION

There will first be described a schematic arrangement of the portabletelephone of the present invention with reference to FIGS. 1 and 2. InFIGS. 1 and 2, there is shown an open condition of a cover of theportable telephone. A case 2 of the portable telephone is comprised ofan upper case 2a and a lower case 2b. A receiver section 4 accommodatinga speaker therein is provided at an upper end portion of the case 2. Adisplay section 6 such as a liquid crystal display and a switch section8 having a dialing function or the like are provided at a middle portionof the case 2. A transmitter section 10 accommodating a microphonetherein is provided at a left end of a lower end portion of the case 2.The reason why the transmitter section 10 is provided at the left end ofthe lower end portion of the case 2 rather than at the center of thelower end portion of the case 2 is that the distance between thereceiver section 4 and the transmitter section 10 is intended to be madeas large as possible in such a compact case 2.

Reference numeral 12 denotes an antenna extendably provided at a sideportion of the case 2. A cover 14 is rotatably mounted in the vicinityof the lower end portion of the case 2. As clearly shown in FIGS. 1-3,the cover 14 comprises a top cover 14-a and opposed side covers 14-b.The side covers 14-b extend generally perpendicular to the top cover14-a. The cover 14 functions to cover at least the switch section 8 whenit is in a closed condition, while functioning as a voice reflecting andcollecting board for the transmitter section 10 when it is in an opencondition. The cover 14 has a shallow concave portion formed in theinside face thereof to facilitate voice reflecting and collecting and aprojection 16 formed on each side cover 14-b to facilitate opening andclosing of the cover. While the cover 14 is rotatably mounted to thecase 2 as mentioned above, it is stably held in position inclined at apredetermined angle with respect to the case 2 by means of a coverholding mechanism which will be hereinafter described.

FIG. 3 is an exploded perspective view of a first preferred embodimentof the cover holding mechanism, and shows a condition where the uppercase 2a is viewed from its back side. The upper case 2a is integrallyformed at its lower end with a cover mounting projection 18 having apair of circular holes 20 at opposite ends thereof. The upper case 2a isfurther formed with a pair of projections 22 adapted to respectivelyengage a pair of U-shaped springs 26 which will be hereinafterdescribed.

Reference numerals 24 denote a pair of shafts for rotatably mounting thecover 14 to the upper case 2a. Each shaft 24 is formed at its one endwith a mounting portion 24a. On the other hand, the cover 14 isintegrally formed with a pair of mounting projections 28 each having ahole 29. The mounting portions 24a of the shafts 24 are adapted to bepress-fitted into the holes 29 of the mounting projections 28 of thecover 14. Further, each shaft 24 is formed at its other end with a pairof annular lands 24b. Between both the annular lands 24b, there isformed an angular plate portion 24c for stably holding the cover 14 at apredetermined inclined angle with respect to the upper case 2a. Theangular plate portions 24c of the shafts 24 are adapted to respectivelyengage the U-shaped springs 26 each having a bent portion 26a at one endthereof.

The cover 14 is mounted to the upper case 2a in the following manner.First, the holes 29 of the cover 14 are aligned to the holes 20 of theupper case 2a, and the mounting portions 24a of the shafts 24 areinserted through the holes 20 of the upper case 2a and press-fitted intothe holes 29 of the cover 14. Then, the U-shaped springs 26 are broughtinto engagement with the angular plate portions 24c of the shafts 24,and the bent portions 26a of the U-shaped springs 26 are brought intoengagement with the projections 22 of the upper case 2a. Thus, the cover14 is rotatably mounted to the upper case 2a.

FIG. 4 shows such a rotatably mounted condition of the cover 14 withrespect to the upper case 2a in vertical section, and FIG. 5 is a bottomplan view of FIG. 4.

The operation of the cover holding mechanism will now be described withreference to FIGS. 6A to 6C. In this preferred embodiment, a stableposition of the cover 14 is a position "b" shown in FIG. 4 where thecover 14 is inclined at 145° with respect to the upper case 2a. In thisstable position of the cover 14, each U-shaped spring 26 tightlycontacts two opposite flat surfaces 25a of the angular plate portion 24cof each shaft 24 as shown in FIG. 6B. An inclined surface 25b is formedcontinuously from one end of each flat surface 25a, so as to permitsmooth rotation of the cover 14.

FIG. 6A shows a closed condition of the cover 14, which corresponds to aposition "a" shown in FIG. 4. In this condition, the U-shaped springs 26operate to press the cover 14 against the upper case 2a through theangular plate portions 24c of the shafts 24. Accordingly, it is notnecessary to provide a lock mechanism for maintaining a closed conditionof the cover 14, and the operability in practical use can be improved.

FIG. 6C shows a fully open condition of the cover 14 obtained against abiasing force of the U-shaped springs 26, which corresponds to aposition "c" shown in FIG. 4. In this condition, the U-shaped springs 26exert a biasing force in a closing direction of the cover 14 through theangular plate portions 24c of the shafts 24, so that the cover 14 isresiliently retained. Accordingly, in an exemplary case such that theportable telephone with the cover 14 open is put on a flat surface suchas a desk surface under the condition where the switch section 8 facesthe flat surface, and that a load is applied to the portable telephonefrom the side of the lower case 2b, the cover 14 is rotated to becomethe condition of FIG. 6C against the biasing force of the U-shapedsprings 26, thus obviating a possibility of breakage of the cover 14. Inthis preferred embodiment, an angle defined between the flat surface 25aof the angular plate portion 24c of each shaft 24 and the cover 14 isset to 55°, so that the cover 14 is stably held in open positioninclined at 145° with respect to the upper case 2a.

While a single stable position of the cover 14 is set by forming theangular plate portion 24c in the vicinity of one end of each shaft 24 inthis preferred embodiment, a plurality of stabilizer points may be setby forming a portion of each shaft 24 in the vicinity of one end thereofinto a polygonal sectional shape. In this preferred embodiment, thestable position of the cover 14 is set in a position where the cover 14is inclined at 145° with respect to the upper case 2a because an S/Ncharacteristic in the transmitter section 10 becomes maximum during thetelephonic communication.

FIG. 7 is a vertical sectional view of a second preferred embodiment ofthe cover holding mechanism according to the present invention, in whicha sectional position corresponds to the line 7--7 in FIG. 5. A pair ofcylindrical members 32 are rotatably inserted through the circular holes20 of the mounting projection 18 of the case 2. A pipe shaft 30 isfixedly inserted in each cylindrical member 32. The pipe shaft 30 isformed at its inner end with a wave cam 40. The pair of cylindricalmembers 32 are fixedly inserted in a pair of mounting portions 34 of thecover 14, respectively. A pair of pins 36 are fixedly inserted throughthe mounting portions 34 of the cover 14, the cylindrical members 32 andthe pipe shafts 30 in a radial direction thereof, so as to preventrelative rotation of the pipe shafts 30, the cylindrical members 32 andthe mounting portions 34 of the cover 14. A spring member 38 formed ofan elastic metal is non-rotatably provided within the case 2. Oppositeends of the spring member 38 are inserted in the pipe shafts 30,respectively. A pair of L-shaped bent portions 38a are formed in thevicinity of the opposite ends of the spring member 38, and they areengaged with the wave cams 40 of the pipe shafts 30, respectively.

When each L-shaped bent portion 38a of the spring member 38 is inpositions where it is seated in trough portions of the correspondingwave cam 40, the spring member 38 is not elastically deformed, and abiasing force of the spring member 38 is therefore not applied to thepipe shafts 30. On the other hand, when each L-shaped bent portion 38aof the spring member 38 is in contact with the vicinity of crestportions of the corresponding wave cam 40, the spring member 38 iselastically deformed in such a manner that the L-shaped bent portions38a are urged inwardly to the center of the spring member 38 in FIG. 7,and the biasing force of the spring member 38 due to such elasticdeformation is applied to the pipe shafts 30.

FIG. 8 is an enlarged view of the wave cam 40 taken in a direction ofarrow B shown in FIG. 7, and FIG. 9 is a front elevation of the wave cam40 shown in FIG. 8. The wave cam 40 has the crest portion 40a, thetrough portion 40b, the crest portion 40c, and the trough portion 40dformed circumferentially in this order. When each L-shaped bent portion38a of the spring member 38 is seated in the trough portion 40b of thecorresponding wave cam 40 as shown by a dashed line in FIG. 9, the cover14 is maintained in a stable position where a plane D parallel to thecover 14 is inclined at 145° with respect to a plane C parallel to thecase 2. On the other hand, when each L-shaped bent portion 38a of thespring member 38 lies on the plane C as shown in a solid line in FIG. 9,that is, when the cover 14 is in a closed condition, each L-shaped bentportion 38a of the spring member 38 is in contact with a portion of thewave cam 40 at a position between the crest portion 40a and the troughportion 40d. Accordingly, the biasing force of the spring member 38 isapplied in a closing direction of the cover 14 through the wave cams 40.

Similarly to the first preferred embodiment, the second preferredembodiment can provide a portable telephone which can obviate apossibility of breakage of the cover and improve the operability inpractical use. According to the first and second preferred embodiments,as the cover 14 in the open position also serves as a voice reflectingand collecting board during the telephonic communication, the S/Ncharacteristic in the transmitter section can be improved. Accordingly,the portable telephone can be made compact by reducing the distancebetween the transmitter section and the receiver section.

According to the present invention, the cover is rotatably mounted tothe case of the portable telephone by the cover holding mechanism.Accordingly, when the cover is closed, the switch section of theportable telephone can be protected by the cover. Further, when thecover is opened, the cover can be stably held in position at apredetermined inclined angle (e.g. 145°) with respect to the case.Accordingly, the cover can be utilized as a voice reflecting andcollecting board, thereby improving the S/N characteristic in thetransmitter section. Thus, the portable telephone of the presentinvention can improve the S/N characteristic will still having a compactsize.

What is claimed is:
 1. A portable telephone comprising:a body having awidth and including a speaker, a microphone and switch means; a coverrotatably mounted at one end to said body to be moveable between openand closed conditions, said cover having a top cover and a pair ofopposed side covers extending generally perpendicular to said top cover,said opposed side covers and said top cover forming a shallow hollowportion in an inside face of said cover, said hollow portion coveringpart of said switch means when said cover is in the closed condition,said cover having a width which is generally equal to or smaller thanthe width of said body; a pair of opposed gripping projectionsrespectively extending laterally outwardly from said side covers, at aposition away from said rotatably mounted ends, for facilitatingmovement of said cover between the open and closed conditions; and coverholding means for rotatably holding said cover with respect to saidbody, said cover holding means including biasing means for exerting abiasing force to said cover so as to resiliently maintain said cover ata stable position in a rotational direction when said cover is in theopen condition and to press said cover to said body when said cover isin a closed condition, said cover being inclined at a predeterminedangle with respect to said body when said cover is in said stableposition; and wherein said microphone is provided in said body at aposition adjacent said cover holding means and said cover functions as avoice reflecting and collecting board for said microphone when saidcover is in said open condition.
 2. A portable telephone according toclaim 1, wherein said cover holding means comprises a cover mountingprojection integrally formed with said body and having a hole; a shaftrotatably inserted through said hole, said shaft having an end portionfixed to said cover and a plate portion with flat sides; and a springfixed to the cover mounting projection of said body so as to nip saidplate portion of said shaft.
 3. A portable telephone according to claim1, wherein said cover has a length and the pair of opposed grippingprojections extend outwardly from said side covers in a direction alongthe length of the cover.